Radiator core



June 23, 1936.

F. A. NEVEU RADIATOR GORE.

Filed Aug. 11, 1954 Patented June 23, 1936 UNITED STATES PATENT OFFICE RADIATOR CORE Frank A. Neveu, Los Angeles, Calif.

Application August 11, 1934, Serial No. 739,453

5 Claims. (01. 252-130) The present invention relates to new and useful improvements in heat transfer devices, and more particularly to that type of radiators which are adapted for use in connection with the cooling systems of automobile engines or other power plants. An object of my invention is to provide an arrangement effecting an increased expanse of radiating surface of the radiating fins of which a radiator is partially composed, whereby to in-- crease the cooling efflciency of the radiator.

It is a further object in this connection to provide such increased radiating surface of the radiating fins without obstructing the air spaces between the passageway-forming tube members, and thereby permit free passage of air through the radiator.

Another object of the present invention is to provide a radiating fin having increased radiating surface as referred to hereinabove, without, however, requiring additional material-in fact, considerably less material is required in a radiator of given size and/or cooling capacity, and consequently the cost of manufacture and weight of the finished radiator is reduced by incorporating the principles of my present invention therein.

Yet another object is to provide a radiator fin of novel design, one of the advantages of which is that-a radiator core embodying it need not be dipped in molten solder, as is now usually done, but instead is subject to being assembled by the baking. process to insure soldering of the sev-.

eral fins to their associated tube members, thereby effecting a great reduction in the amount of solder required in the construction of a core.

The invention possesses other objects and advantageous features, some of which, with the foregoing, will be set forth in the following description of the embodiments of my invention which are illustrated in the drawing accompanying and forming a part of the specification. It is understood that I do not limit myself to the showing made by the said drawing and description, as I may adopt variations of the described forms within the scope of my invention as": set forth in the claims. r

Referring to the drawing: Figure 1 is a fragmentary view in perspective showing a portion of a radiator core of the honey-comb? or cellular? type, having incorporated therein a fin embodying the principles of the present invention.

Figure 2 is a perspective view showing a small portion of a modified form of fin, also intended for use in a radiator of the cellular type.

Figure 3 is a fragmentary, perspective view showing the radiating fin of the present invention adapted for use in the tubular type of radiator. Portions of the figure illustrating the front of the radiator are broken away the better to show the interior construction.

In terms of broad inclusion, my present invention contemplates the use of metal fabric, or 10 wire mesh, as the material used in the construction of radiating fins for a radiator, instead of the sheet metal commonly employed for this purpose. 1

More specifically described, the improved radi- 15 ator fin of the present invention comprises a sheet of wire fabric, preferably copper screen of suitable size of mesh, and composed of screen wire of suitable gauge and preferably round in cross section. The wire fabric is cut to proper 20 size and bent to proper shape to meet the requirements of the radiator fin. This improved form of fin is adaptable for use in either the cellular type or the tubular type of radiator, and is susceptible to being formed into any size 25 and/or shape of fin in order to meet the requirements of any particular installation. Wire screen is available commercially in sheet form, and, on account of the smaller amount of metal necessary to form a sheet of given size, is con- 30 siderably less expensive than sheet copper, which is the material now commonly employed in the manufacture of radiator fins. Of more importance, however, is the superiority of a radiator fin made of wire mesh from the standpoint of 35 heat-radiating efiiciency as compared with a more conventional sheet metal fin.

This increase in efliciency is due to the large number of foramina defined by the interwoven wires of metal fabric such as copper screen, inas- 40 much as their presence insures much more intimate contact of the air flowing through the air passages between the tube members of a radiator core with the metal of the fin.

It .is common practice in making fins from sheet metal to deform the sheet with a large number of protrusions, corrugations, restrikes, blades, and the like, and to cut openings of various size, shape, and position in the sheet in the attempt to develop a great amount. of turbulence 50 in the stream of air flowing through the core, aswell as to cause contact of the flowing air with the metal of which the core is made. The purpose of resorting to such expedients is to remove as great a quantity of heat-from the metal con-' a construct radiator fins has never before been resorted to; whereas by its use, the problem of providing means for insuring the very greatest degree of intimate contact with the metal has been met, and moreover, without interfering with or 'with the thickness of the finished core.

impeding the flow of air through the air passages. The air is caused to pass through a much higher number of orifices than can possibly be formed in any sheet metal fin, thereby reducing the blast of air to a very large number of very fine streams of air, each of which is in very close contact with the wires defining the orifice through which that stream is flowing. Each of the many wires forms a cutting edge against which the air impinges, thus causing-the intimacy of contact which can be developed only by means of a cutting edge exposed to air flow, and also causing turbulence, the effect of which is to direct the flow of air out of a straight path and into contact with a neighboring portion of a water tube, another fin, or another section of the same fin. These facts are believed to explain partially the superiority of wire screen in the manufacture of radiator fins over sheet metal used for that purpose.

Moreover, these advantages and others can be gained without sacrifice of any of the advantageous features of sheet metal. If the design of any particular make of radiator core calls for any particular configuration of fin, the wire screen is just as susceptible to being so formed as is the more conventional sheet metal. any desired size, shape and/or spacing of tube members may be resorted to, the fin being cut, bent, and/or otherwise formed into whatever size and shape of fin is desirable with the selected tube members. v

Figure 1, for example, shows a small portion of a radiator core 6 made up of alternately positioned water tube members 1 and radiating fins 8, the latter of which being comprised of inter- ,Woven wire 9 of metal, preferably copper, embody the principles of my present invention. Whereas the fin is adaptable to any suitable type of water tube member, each of the tube members I illustrated is made up of a pair of elongated strips II and |2 of copper the width of which coincides Alon-g their edges l3 the two strips are in contact-with each other and are bent to zig-zag form, whereas intermediate their edges, the strips are separated to define a water channel l4 therebetween. -The water channels |4 thus presented establish communication between the upper and lower header tanks (not shown) in accordance with usual practice, and hence, during operation of the device, each channel M has a stream of heated water to be cooled flowing through it. In order to induce turbulence in the stream of water in each channel l4, and thus cause more of the heat of the water to be transmitted to the metal of the tube member, it is customary to deform the metal defining the water channels, as, for example, by providing transversely extending corrugations IS in any of several arrangements.

Here the crest of each outwardly extending corrugationis preferably flattened as indicated at H. Each of these flattened crests I1 provides Hence an area of material size contacting the associated fin 8, thereby increasing the efficiency of heat transference from the tube member to the wires of the fin, which, as will readily be understood, are very highly efficient in transferring the heat to the air impinging thereagainst.

The preferred form of fin 8 for use with this type of tube member, when composed of interwoven metal wires as hereinabove .disclosed, is also deformed to present a series of corrugations, but,v instead of extending transversably as has heretofore been the practice, the corrugations 2| of each fin 8 extend longitudinally of the core, preferably throughout the entire length thereof from the upper header tank to the lower. The

corrugations 2| serve to increase the efiectiveno impedance is offered thereby to the flow of airthrough the channel 22,- in spite of the fact that very intimate contact of each particle of air with the wires of the fin is had a number of times equal to twice the number of corrugations 2|.

With the illustrated type of tube member I, it is preferable to use a fin 8 wherein the corrugations 2| .also are flattened at their crests 24 thus forming corrugations 2| which are substantially square in cross section, and presenting relatively large areas of contact between each flattened crest ll of each corrugation l6 ofthe proximal tube member I. However, Figure 2 illustrates a modified form of fin 3| adaptable for use with various other well known types of tube members of a cellular type core, but also embodying the present invention inasmuch as it also is constructed of wire fabric 32. This fin 3| is also corrugated, but it difiers from the previously described fin 8 in that its corrugations 33 extend transversably instead of longitudinally and each corrugation 33 is of triangular cross section.

In order to facilitate assembly it may in some instances be advisable to provide slight irregularities-in the surfaceof each tube member adapted to be engaged by complementary irregularities in the surface of the proximal fin, thus serving as locators tending to hold the several members against slipping one on the other prior to and during the soldering process. Such locators are illustrated in Figure l as taking the form of a depression or socket member 36 at each end of each crest l6 of the tube members, within which sockets are seated, raised portions or beads 31, one of which is formed along the outeredge of each outer corrugation 2| of each fin 8.

Each

Figure 3 illustrates my present invention emwoven wire fabric 43, extends transversably of the tubes 44, each tube 44 extending through an aperture 4B in each fin, these apertures being suitably proportioned to insure contact between each tube 44 and each fin 42. The extent of such contact can be materially increased by extending flaps 41 of the metal fabric displaced in forming each aperture along the adjacent side wall 48 of the associated tube 44. Moreover, I prefer to bend the forward edge 5| of each fin 42 so as to form a flap 52 lying in a plane perpendicular to that of the remainder of the fin and extending into contact with'the next adjacent fin. In this manner, the front of the radiator presents the appearance of a continuous, fiat wire screen, concealing the tubes 44 therebehind" and requiring that all the air passing through the air passages between tubes flow through the relatively fine apertures presented by such a screen.

It is customary commercial practice in assembling cores using fins made of sheet metal to.

fasten the parts permanently together by dipping the assembled core in a bath of molten solder, causing the fins to be soldered to the tube members in an integral structure. It is preferable, however, when using fins embodying the present invention, to avoid the dipping process of soldering, as such method would have the tendency to clog the openings of the screen of which each fin is made. Rather, a baking process should be used, wherein each tube member is tinned before assembly, and after assembly the core dipped in a suitable acid or flux, and then the entire core placed in an oven or the like where its temperature is raised higher than the melting point of the solder. The solder already present on the tube members will flow onto the portions of the fin in contact therewith-forming a sweated joint fully as efiicient from the standpoints of strength and heattransference as a dipped joint and requiring so much less solder as to amount to a saving of from one to four or more pounds of solder per core, depending on the size of the latter. The saving in weight thus attained is material, but

the reduction in cost of the core is of still greater frelation, and a radiating fin disposed between each two adjacent tube members, each of said fins being composed of wire screen and corrugated to provide corrugations having their crests alternately on opposite faces of the fin, said crests making contact with the associated tube members, and said corrugations extending substantially parallel to the direction of flow through said tube members thereby disposing the side walls of the corrugations in positions extending across the air passages between said tube members.

2. A radiator construction comprising a plurality of tube membersdisposed in spaced parallel relation, and a radiating fin disposed between each two adjacent tube members, each of said fins being composed of wire screen and corrugated to provide corrugations having their crests alternately on oppositefaces of the fin, said crestsmaking contact with the associated tube members, and said corrugations extending substantially parallel to said tube members thereby disposing the side walls of the corrugations in positions extending across the air passages'between said tube members, said tube members having irregularities in the surfaces thereof and said fins having irregularities in the surfaces thereof complementary to and engaging those of said tube members to restrain said tube mem. bers against movement relatively to said fins prior to permanent fastening thereof.

.3. In a radiator construction, a core comprising a plurality of wire mesh fins disposed in spaced parallel relation, and aplurality of tube members spaced apart, each of said tube members extending through and making contact with all r of said fins, said fins being bent adjacent their forward edges and each fin so bent making contact with the next adjacent fin to present a substantially continuous screen extending across the front of said core.

4. In an automobile radiator, a core comprising water tube members spaced apart to define passages through which a flow of air in a predew termined direction is induced, said water tubes extending angularly with respect to the direction of said air fiow, and a fin of foraminous material interposed between each two adjacent water tube members, and-corrugated to define corrugations having their crests alternately on opposite faces of the fin, said corrugations extending substantially parallel to said tubes and angularly with respect to the direction of said air fiow, the crests of said corrugations contacting the associated tube members and the side walls of the corrugations extending across said air passages, whereby saidfiow of air is required to pass through the foramina in said side walls.

5. In a radiator construction, a core comprising a plurality of fin members of foraminous ma terial disposed in spaced, parallel relation, and a plurality of tube members arranged in contact withosaid fins for transmission of heat therebetween, said fins being bent adjacent edges there- 'of to present po'rtions lying in the plane of the associated face of said core and contacting the nextadjacent member whereby all air going through the spaces between saidtube members is required to fiow through at least one thickness of said foraminous material.

- FRANK A. NEVEU. 

